¥8,200,000 (Direct Cost : ¥8,200,000)

Radiochemical studies of various aspects of nuclear reactions such as spallation, fission and fragmentation have been performed at low to high energies by using photons, neutrons, protons, and heavy ions from available accelerators in Japan, and discussed together for reaction mechanism and their possible applications.Photopion reactions photospallation, photofission and photofragmentation of 22 targets ranging from ^<27>Al to ^<201>Bi at 60-1000 MeV were extensively studied by Sakamoto, Fujiwara and Shibata. Recoil measurements of Cu-spallation and Au-fission were included. Masumoto and Ohtsuki measured the depth and angular profiles of spallation products in a 250 cm concrete shields for Tohoku Univ.e-linac. This accelerator was used by Sakamoto group and Mitsugashira who reported studies of photofission of ^<237>Np and production of ^<242>Cm and ^<238>Pu in a high-flux reactor JMTR.Recoil range measurement was performed by Sekine, in which a new thin foil method was developed. He al
… Moreso studied recoil synthesis of labelled compounds by (n, g) and (g, n) reactions. Heavy ion-induced spallation upto GeV energies was extensivly studied by Shinohara who also continued an important study of pi-mesic atom chemistry at KEK PS.Momentum transfer in nuclear processes is a very important information, and investigated in heavy-ion-induced reactions by Shinohara and also in proton-induced fission of^<238>U and ^<232>Th by Kudo. Neutron- and Proton- induced reactions producing light nuclei like ^<7,10>Be at several tens of MeV are of vital importance in many applications, and several results of excitation functions were reported by Imamura and Shibata. An extremely sensitive measurement of long-lived radionuclides has been established by Kobayashi, Nagai and Imamura, and successfully applied to some of the above-mentioned reaction studies. Combined discussions were performed by exchanging information obtained during the course of the present project, and our prospects for further developments in this field have been exploited. Less